Piston



c. E. JOHNSON Apr. 24, 1923.

PISTON Filed Sept. 1, 1922 1171 61? for;

Patented Apr. 24, 1923.

UNIT-ED time? CHARLES E. JOHNSON, OF MUSKEGON, llTICI-IIGAN, ASSIGNOB TO THE PISTON RING COMPANY, OF MUSKEGON, IiZICE-IG-ILN, A CORPORATION OF MICHIGAN.

PISTON.

Application filed September To all whomit may concern:-

Be it known that 1, CHARLES E. Jonnson, a citizen of the United States, residing at Muskegon, in the county of Muskegon and State of Michigan, have invented new and useful Improvements in Pistons, of which the following is a specification.

The present invention relates to pistons; and its object is to provide a piston having a body member and a surrounding sleeve member, with improved means whereby leakage between said members may be prevented.

This and any other objects appearing hereinafter are attained by, and the invention finds preferable embodiment in, the structure hereinafter particularly described in the body of this specification and illustrated by the accompanying drawings, in which Figure 1 is a view of a piston, partly in top plan and partly in transverse section taken on line 1-1 of Figure 2;

Figure 2 is a view of the same partly in side elevation and partly in axial section taken on line 2-2 of Figures 1, 3, and 4t, and showing in like section a portion of the cylinder containing the piston;

Figure 3 is a view of the piston, partly in top plan and partly in transverse section taken on line 33 of Figure 2; and

Figure & is a bottom plan view of the piston.

In the embodiment of the invention chosen for illustration by the drawings and for detailed description in the body of this specification, a piston reciprocating in 2. cylinder 1 of an internal-combustion engine is shown.

This piston comprises a body member 2 carrying the piston pin 3 on which is rockably mounted the piston rod (not shown) the piston comprises also a sleeve member t surrounding the body member, and being resiliently expansive, bears on the interior of the cylinder. The body member has at one end a radially-extending continuous flange 5 against which the corresponding end 6 of the sleeve member abuttingly contacts tightly. The sleeve member is held in such contact with this flange in any suitable manner, as by the mutual engagement of the radially'extending portions 7 of the 1, 1922. Serial No. 585,587.

body member and 8 of the sleeve member.

rrs seen in lflgures 2 and 4, these portlons 7 are spaced apart angularly and the portions 8 are similarly spaced, so that in assembling the two members 2 and 4t, the portions 7 are passed between the portions 8 as the members 2 and 4t are interrelatively moved in their axial direction, whereupon these members are interrelatively turned about their common axis, so that said portions are moved to their mutually engaging position seen in Figures 2 and 4. The portions 8 of the sleeve member may have inclined surfaces 9, as shown, so that the sleeve member may be expanded to permit its assembling with the body member by being pushed over its lower end, whereupon the sleeve member contracting will cause the portions 7 and 8 to lockingly engage.

The sleeve member is resiliently expansible and contractible, having a longitudinally-disposed slit 10. In order to prevent leakage past the piston and between its body member and sleeve member, the sleeve member is provided with a recess 11 extending across the slit 10. This recess extends inwardly from the sleeve members curved outer side to the bottom wall 12 of the recess, and from the end 6 of the sleeve member (which end abuts the body members flange 5) to the side wall 13 of the recess. A dam plate 14 in the recess extends across the slit 10 and tightly fits the bottom wall 12 and the side wall 13 of the recess, and is slidable in the recess, on at least one side 15 of the slit, in a direction transverse to the slit.

The dam plate 1d may be held in place in the recess as by welding or by a rivet 16.

It will be seen that although the sleeve member may expand or contract in its diametrical direction, leakage past the piston and through the slit 10 is prevented by the dam plate. r

The recess 11 may be formed with a smooth flat bottom wall 12 and a flat smooth side wall 13 by an end-mill; and after the dam plate is secured in the recess as by the rivet 16, any portion of the dam plate protruding from the recess either in the axial or transaxial direction of the sleeve member may be turned down in a lathe.

The invention being intended to be pointed out in the claim, is not to be limited to or by details of construction of the particular embodiment thereof illustrated by the drawings as hereinbefore shown or described.

I claim:

In a piston; a body member having a radially-extending flange; a sleeve member surrounding the body member and having a longitudinally-disposed slit, and a recess extending across the slit and inwardly from the sleeve members outer side to the bottom wall of the recess and from an end of the sleeve member to the side wall of the recess; a dam plate in the recess extending across the slit and tightly fitting the bottom Wall and the side wall of the recess, and being slidable in the recess on at least one side of the slit in a direction transverse to the slit; means for holding the body 'members flange in tightly fitting contact with said end of the sleeve member and with the outer edge 8f the dam plate.

In testimony whereof I have hereunto set my hand at Grand Rapids, Michigan, this 23rd day of August, 1922.

CHARLES it. JOHNSON. 

